Knee Joint is the largest joint in the human body and one of the most easily injured. The knee joint is a hinge type synovial joint, which mainly allows for flexion and extension (and a small degree of medial and lateral rotation).
The knee contains three bones Femur, Tibia and Kneecap, two meniscus (medial and lateral) absorb shocks by increasing surface area to further dissipate forces, hyaline cartilage covering the bone surface, two tendons patellar tendon and quadricipital tendon and several ligaments with stability function.
- The anterior cruciate ligament (ACL) located in the center of the knee controls rotation and forward movement of the tibia.
- The posterior cruciate ligament (PCL) as well, located in the center of the knee controls rotation and posterior translation of the tibia.
- The Medial collateral ligament (MCL) resist outward turning forces on the knee.
- The Lateral collateral ligament (LCL) resist inward-turning forces on the knee.
All these structures are susceptible to be injured affecting the knee functions, the main injuries are:
- Ligament sprains are graded into 3 grades by the amount of stretching or tearing of the ligament fibres and how much instability it causes.
- Bones fractures.
- Arthritic changes and cartilage lesions.
- Meniscal tears.
- Patella dislocation.